Outboard motor water pump



1951 L. T. KINCANNON 2,536,374

OUTBOARD MOTOR WATER PUMP Filed Aug. 4, 1949 INVENTOR. g, 7, @Wm BY 6:44 offimee.

Patented Jan. 2, 1951 OUTBOARD MOTOR WATER PUMP Leo T. Kincannon, Milwaukee, Wis, assignor to Metal Products Corporation, Milwaukee, Wis., a corporation of Wisconsin Application August 4, 1949, Serial N 0. 108,489

1 Claim. 1

The invention relates to water pumps for outboard motors and more particularly to flexible vane pumps having an eccentrically disposed cam surface for flexing the vanes as they pass from the inlet to the outlet portions of the pump.

Heretofore, in pumps of the type above described, the rotor has been provided with a series of equally spaced radially disposed vanes about its periphery, as shown for example in my prior U. S. Patent No. 2,460,421, of February 1, 1949. In such pumps the suction at the inlet is practicaliy continuous, and as a result it has been found that when such pumps are used on outboard motors .in Waters containing weeds, the weeds soon clog the inlet to the pump and render it ineffective to supply the necessary coolant to the motor. After considerable experimenting, I have found that pumps of the general character above described can be made to operate on outboard motors in weedy water by changing the rotor construction so that instead of the pump acting as substantially continuous pressure pump, it has a pulsating action, so that during each rotation of the rotor the suction pressure is cut off, thus allowing weeds or other foreign matter tending to clog the inlet to be forced off by the action of the motor as drives the boat through the water. More particularly, the object of the present invention is to provide a pump rotor for water pumps for outboard motors in which the flexible vanes or blading only extend from a portion of the hub of the rotor and there is an open space between this blading sufficient to bridge the space between the inlet and outlet of the pump which on each revolution of the rotor acts to remove the suction at the inlet and permit the washing off of weeds from the inlet. Furthermore, the space between the blading above referred to permits ready draining of the water from the cooling system which prevents freezing of the cooling system in cold weather.

The invention further consists in the several features hereinafter described and more particularly defined by claims at the conclusion hereof.

In the drawings:

Fig. 1 is an elevation view of the lower end of an outboard motor assembly, parts being broken away through the pump portion thereof and shown in section along the broken line ll of Fig. 2;

Fig. 2 is a View of the pump with its cover plate removed;

Fig. 3 is a view similar to Fig. 2 showing the pump housing and its cover plate.

Referring to the drawings, the numeral 5 designates a portion of a propeller drive shaft housing for an outboard motor having a threaded tubular end 5, a shouldered bore 1, and an annu lar chamber 8 formed therein provided with an outlet Q forming part of the motors cooling system.

The propeller drive shaft in extends through a bearing H, and a packing washer I2 mounted in the bore '5 and has the propeller 13 mounted thereon.

A cylindrical cup-shaped housing It is provided with a closed end l5 through which the shaft It extends and has a cylindrical bore l6 and a threaded bore l1 formed therein. The end I5 is provided with a series of water inlet slots IS.

A generally tubular liner member IQ of brass, bronze, or other suitable material fits closely within the bore it except for a chordwise or flattened portion 20, shown in Fig. 2, to provide a cam or eccentric surface at this portion of the casing which reduces the volume of the chamber 2! formed by said housing, liner, and a removable cover plate 22 which abuts the inner edge of said liner, and is clamped against the same when the housing It is screwed up onto threaded portion 6 of the housing 5. The cover plate 22 has a slot 23 forming an outlet, and in order to properly register this outlet relative to the inlet ll, said plate has a key 24 registering with a key slot 25 in the housing l4.

While the inlet I3 is the inlet to the housing It, the actual inlet 26 is formed between a flanged ring 21 carried by the housing l4 and a tubular extension 28 of the hub of the propeller [3 though it will be understood that instead of the annular inlet thus formed, a side inlet passage may be provided.

Within the chamber 2| and suitably keyed to the shaft It is a vane type rotor or impeller 29 formed of suitable rubber composition or other suitable flexible material whose vanes 30 are equally spaced about a portion of its periphery and are capable of flexing relative to each other so as to reduce the space between them and thus provide a contractible chamber from which the water taken in between the vanes at the inlet [1 is expelled through the outlet 23 as said vanes are flexed by their engagement with the flattened portion 26 of the liner.

Referring particularly to Fig. 2, it will be noted that unlike the rotor of my prior patent the blading does not extend about the entire periphery, but that there is an open space 3| between the blading of a length at least suflicient to establish free communication between the inlet l1 and the outlet 26 of the pump, so that when the rotor is in the position shown in Fig. 2, the pump suction is relieved with the result that any weeds which may collect about the inlet 26 will not adhere thereto by the suction effect of the pump but will be washed off by the forward movement of the motor in the water through which it is passing. As herein shown about twenty-five per cent of the blading of my prior patent has been eliminated to secure the best results. It has been found that this change in the rotor construction over that of my Patent No. 2,460,421 eliminates any chance of weeds clogging the inlet of the pump and interfering with its proper operation of furnishing coolant to the motor through the outlet 9 as the propeller shaft l revolves.

While I have shown the impeller of the pump as mounted on the drive shaft I0 that carries the propeller in some outboard motors, pumps of the general type above described are mounted on the drive shaft that extends from the crank shaft of the motor down to and has a drive connection with the propeller drive shaft, and this invention can be used on impellers Where the pumps are installed on this last described form of drive, in each instance it being noted that the shaft which carries the impeller is an underwater drive shaft and that term has been used in the claim to apply either to the propeller shaft proper or the shaft that is usually vertically disposed thereto and drivingly connected therewith. I desire it to be understood that this invention is not to be limited to any particular form or arrangement of parts except in so far as such form contractible and expansible chambers be-' tween adjacent blades as they traverse said outlet and inlet, certain of said blades being spaced apart a distance greater than the distance between said inlet and outlet so that during a portion of a revolution of the impeller the inlet and outlet are in communication with each other to relieve the suction and thereby prevent foreign matter obstructing the operation of the pump.

' LEO T. KINCANNON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,189,356 Briggs Feb. 6, 1940 2,203,974 Weinhardt June 11, 1940 2,460,421 Knca'nnon Feb. 1, 1949 2,460,952 Simer et a1 Feb. 8, 1949 2,466,440 Kiekhaefer Apr.. 5, 1949 

